Ivy Rutzky, a senior scientific assistant and illustrator at the American Museum of Natural History, has given us a start by outlining what the shark's head and body shapemighthave looked like based on the braincases that have been found. We want you to take it from there.

Remember: Ancient sharks didn't all look alike, not by a long shot. Scientists believe sharks during the Devonian Period were much more diverse than today, with perhaps many different species, colors, shapes and sizes of shark inhabiting the oceans.

The expedition team searching for the 400-million-year-oldPucapampellashark are at a bit of a disadvantage: They don't know what it looked like.

Nobody does. So far, only two "braincases" and perhaps a fin have been found, leaving scientists to imagine what this important little shark-thing resembled. They can guess at its shape and size, but won't know for sure
until they find more fossil evidence.

They do know thatPucapampellaswam in the cold southern ocean a long, long time before the first dinosaur walked on land. And they're fairly certain that it was on the smallish side, perhaps as little as a foot long. Scientists also assume that the snout was snub, consistent with other early sharks (longer "shark noses" came later).

It's possible that this Falklands expedition will uncover fossils that could help solve thePucapampellapuzzle. But for now, let's dream a bit. Take a look at the image to the upper left.Then make your own shark and share it with family and friends.